Gift boxes usually are made of cardboard and arranged so that they are folded flat prior to use. This is important in minimizing space requirements for shipment and storage. The boxes are formed as identical units that are fitted together, one to form the lid and the other the receptacle portion of the box. Each unit is made of a sheet of cardboard having a rectangular bottom panel with edge panels doubled over the bottom panel when the box unit is folded. The ends of the edge panels are connected by end flaps on one opposite pair of the end panels, which are joined by an adhesive to the adjacent ends of the other pair of edge panels. When the box is unfolded and the edge panels moved to an upright position relative to the bottom panel, the bottom edges of the end flaps engage the bottom panel, thereby providing support to the edge panels. Without this support, the edge panels would not remain erect and would collapse back inwardly toward the bottom panel.
Undesirably, however, the bottom edges of the end flaps must be recessed, so that they allow an excessive inward inclination of the edge panels. In other words, as conventionally supported by the end flaps, the edge panels are far from being perpendicular to the bottom panel. This causes difficulty in placing the contents into the box, as well as detracting from the appearance of the box and adding to the complexity of fitting the two box units together.
The recessing of the bottom edges of the end flaps comes about because of the scores at the intersections of the edge panels and the bottom panels. Scores are necessary so that straight bends can be formed when the edge panels are deflected to the folded position, as well as to the upstanding position for the completed box. These scores are made by steel rule dies which distend the material of the box upwardly as ridges along the surface of the bottom panel against which the edge panels are bent. A corresponding groove is formed in the opposite side of the board along each of the score lines. As a result, when the edge panel is bent relative to the bottom panel, the ridge protrudes into the space between the two at the base of the bend. In the folded box, the end flaps must fit within this space. Because of the presence of protrusions formed by the ridges of the scores, the bottom edges of the end flaps must be recessed sufficiently to provide clearance. This recessing is enough to prevent the end flaps from supporting the edge panels in anything approximating a perpendicular position relative to the bottom panel.